cooper



N0. 625,02l; Patented May l6, I899.

. COOPER.

srmocx.

icq ion filed Dec. 27, 1898.)

(No Model.) 2 Sheets$heat 2.

NlTED STATES PATENT OFFICE.

THOMAS COOPER, OF KINGS LYNN, ENGLAND.

TH RUST-BLOCK.

SPECIFICATION formingpart of Letters Patent No. 625,021, dated May 16,1899. Application filed December 2 7, 1898. Serial No. 700,415. (N0model-) To all whom it may concern:

Be it known that I, THOMAS COOPER, engineer, of The Elms, Kings Lynn, inthe county of Norfolk, England, have invented certain new and usefulImprovements in Thrust- Blocks for Propeller and Similar Shafts, ofwhich the followingis a specification.

The object of the present invention is to facilitate the employment ofantifriction-rollers in thrust blocks or bearings used in connectionwith propeller and similar shafts.

The main difficulty to be surmounted in attaining the above objectarises from the failure of the rollers to withstand the pressure of thethrust combined with the high rate of speed at which they are calledupon to run.

It would appear that antifriction -rollers which when carrying a givenload will last well when run at a low rate of speed will fail veryquickly under the same load if run at a high rate of speed, as isnecessary when a propeller-shaft is driven at the ordinary full speed.This being so, I have directed my attention to the production of meanswhich will relieve the rollers from an undue rate of speed, while thepropeller-shaft continues to be driven as fast as or even faster thanhitherto. Accordingly I employ between the collar of the propeller-shaftand the fixed abutment a series of sets of antifriction-rolls,and'between the sets I place a disk or plate of metal capable of turningloosely on the propellershaft. These plates turn or are turned upon theshaft at different speeds. That nearest the propeller-shaft collarrotates at the highest speed, but more slowly than the shaft, and thatnearest the fixed abutment at the lowest speed, and those between atrates corresponding to their position between the two end plates. Forinstance, supposing six sets of rolls to be employed there will be fiveintermediate disks dividing the sets. For the sake of example I willtake the speed of rotation of the propeller-shaft collar at six units,the disk nearest thereto will be driven at five units, the next at four,the next at three, the next at two, and the last nearest the fixedabutment at one. It will thus be seen that each set ofantifriction-rollers has only to turn at a speed equal to the differenceof r0- tation between the two adjacent surfaces,

embodying my invention.

or a disk and the fixed abutment; In this manner the speed of rotationof the propeller is divided up and distributed among the six sets ofantifriction-rollers, so that none are subjected to an injuriously highrate. The number of sets of rolls and disks may be increased'ordecreasedto suitvarying requirements. g

In the accompanying drawings, Figure 1 shows in a longitudinal section athrust-block Fig. 2 is a face view of a detail detached, as hereinafterexplained; and Fig. 3 is a transverse section on line X X of Fig. 1.

A is the propeller-shaft, and at is a collar fast thereon.

B is a fixed abutment, betweenwhich and the collar a is arranged theantifriction device embodying my invention. 1) is another abutment,which maybe connected to the abutment B by means of bolts or otherwise.This abutment b is intended to take the back: thrust when the engine isreversed.

c, o, 0 c and c are the disks above mentioned, each of which isfurnished withan nular races for the antifriction-rollers d. Theantifriction-rollers d are by preference carried in cages 1), (shown atFig. 2,) arranged between the disks, and are free to turn with thepropeller shaft, upon which they are threaded. The rollers, which aretapered, are

fitted into recesses in' the cages, which recesses, according to animprovement which forms part of the present invention, I prefer toarrange in two or more concentric rings or annular series, although thisarrangement is not in every case essential. This enables me to obtainwith, say, two rings or annular series of short rollers of any givendiameter a greater total of roller length than can be procured whenrollers of double the individ ual length arranged in a single ring ofrecesses are employed, and, moreover, the lateral thrust incidental tothe employment of long tapered rollers is thus diminished.

The differential driving of the intermediate plates may be obtained invarious ways. One way which will be found to answer satisfactorily,however, consists in the employment, as shown in Fig. 1 of the drawings,of gear= teeth upon the propeller -shaft collar CL and either disks or adisk and the propeller-collar upon the periphery of the disks 0, 0', c c

and c and of a train of pinions e e e e e e e e e", engaging therewithin such a way as to drive the disks at the required differential speedwhen the propeller-shaft rotates. These pinions may conveniently bemounted in pairs upon shafts E, threaded through bearings carried by theroller-cages.

There maybe more than one set of pinions arranged at intervals aroundthe circumference of the disks, (two are drawn in Fig. 1 and four areindicated in Fig. 2;) but the number of sets employed will be inaccordance with the requirements of each case.

The last of the cages-via, that marked D* in the drawings (see Fig. 3)isprovided with a brake-band F, having an adjustable setscrew f. Theobject of this brake is to prevent the whole series of geared disks andcages from becoming locked together, and thereby throwing all the workon the last set of rollers only. Instead of having a brake the last cageD" may, if preferred, be'geared to the disk 0 and to the fixed abutment,so as to regulate its speed of rotation to the requisite both work welland wear well and will insure in the case of propeller-shafts theimmunity from endway friction, which is easily attained by means ofrollers in bearings for shafts of lighter and smaller caliber for otherpurposes.

I claim l. A thrust-block for propeller and similar THOMAS COOPER.

Witnesses:

H. K. WHITE, H. F. GoLTZ.

